Elastic fluid turbine



Oct. 13, 1931. G. WEIDEHOFF ELASTIC FLUID TURBINE Filed June 17, 1929 Inventor* Georg Wedeho; b5 um HsAttorr-xe.

Patented Oct. 13, 1931 UNITED STATES PATENT OFFICE GEORG WEIDEHOFF, F CHARLOTTENBURG, GERMANY, ASSIGNOR TO GENERAL ELEO- V TBIC COMPANY, A CORPORATION 0F NEW YORK ELASTIC FLUID TURBINE Application filed June 17, 1929, Serial No. 371,694, and in Germany July 12, 1928.

The present invention relates to elastic fluid turbines and especially to elastic fluid turbines comprising a single-flow element and a double-flow element mounted on a common shaft.

ln a turbine installation composed of a single-flow turbine element and a doubleflow turbine element, an axial thrust is pro duced on the shaft owing to the push exerted by the single-flow turbine element, even if the double-fiow turbine element is fully balanced. This axial thrust is produced irre spec'tive of whether the single-flow element is rovided with impulse or reaction blades. y n impulse turbines this thrust occurs usually owing to small steps on the shaft between the internal stuffing boxes of the individual stages, and also occurs when said stuffing boxes are of uniform diameter.

According to the present invention this axial thrust is balanced by totally or partial ly providing the portion of the double-flow rotor facing the single-flow element, accordingto necessity, with reaction blades; or by subjecting one rotor portion of the doubleflow element to additional steam pressure.

V7 hen both portions of the double-flow turbine element are provided with reaction blades, the portion of the double-flow rotor which is opposite the single-flow element may be given a more intensive reaction than the remaining portion of the said rotor; or it maj,7 likewise be subjected to additional steam pressure which counteracts the axial thrust.

Figure 1 of the drawings is a longitudinal section through a turbine installation, the singlesflow and double-flow elements of which are disposed on a common shaft.

Figure 2 is a partial view of the doubleflow rotor of a low-pressure turbine.

Referring to Figure l, a single-flow impulse liigh-pressure turbine clement a is mounted on a common shaft with a doubleflow low-pressure turbine element b likewise 4o provided with impulse blades. The two portions c and d of the last mentioned turbine element are balanced one relatively to the other. There isJ however, a certain amount vof pressure which acts in a direction toward the right in Figure l due to the axial thrust of the turbine element a, and to balance this.

there is provided an opposing pressure which is exerted on the first disc wheel hV of the portion of the double-flow element opposed to the single-flow turbine element. This pressure is produced by providing a suitable pacling e between the first nozzle ring and the first rotor wheel and yan aperture g opening into the space between the first rotor wheel and the adjacent partition wall 7c whereby elastic fluid of the same pressure as that supplied to the first stage nozzle is supplied to such space. An equal amount of pressure cannot take effect before the first wheel z' of the double-flow portion 0 because the stem in this portion must flow through the first row of nozzles before reaching the space in front of the disc wheel z'.

Instead of exerting steam pressure on a turbine disc-wheel, the axial thrust may be balanced, as shown in Figure 2, by fitting reaction blades f to the double-flow portion d facing the high-pressure element a, the other low pressure portion c being provided with impulse blades. The extent of the reaction to be given blades f is governed by the amount of axial thrust exerted by the high-pressure element a.

Vhat I claim as new and desire to secure by Letters Patent of the United States, is:

l. A turbine installation comprising a high pressure single-flow element and a lowpressure doubleflow element. said elements having separate casings and being mounted on a common shaft, said double fiow element having its two sections arranged with their high pressure ends adjacent to each other, and with a common elastic fluid supplyT chamber, and means for subjecting one of said two lowpressure sections to an axial pressure greater than that to which the other section is subjected for balancing the axial thrust of the single-flow element.

2. The combination with a turbine installation comprising a single-flow element and a g5 double-flow7 element mounted on a common shaft, said double-flow element having a common space from which elastic fluid is supplied to both portions in opposite directions so as to counterbalance the axial thrust of no kthese portions, of means for supplying elastic fluid from said space to the rst disc Wheel of one of said portions to produce on it a pressure of a value such as tobalance the axial fthrust ofthe single-flow element.-r 3. The eombinationwith a turbine insta-lla- 'tion comprising vra single-flow 'element and Y Y afdoubleilow element mounted on a common j shaft,V said double-HOW element having a Wall Awhich separates oneportion from the other and a common space from which elastic Huid j is supplied to both portions in opposite directions so as to counterhalance the axial thrust ofthese portions, of means providing a conduit for supplying elastic Huid from said space to the spacebetween said Wall and the yirst disc Wheel of one .of said portionsrfer producing on such :portion .an axialthrust suchas to balance the axial thrust of the single-flow element. l

`In Witness whereof, I have hereunto set my hand this 28th dayofl May, 1929.

' f GEORG WEIDEHGFF. 

